//创建自己的函数时,必须自行处理这3个方面--定义,提供原型和调用.

#include<iostream>
void simple();  //function prototype(函数原型)

int main()
{
    using namespace std;
    cout << "main() will call the simple () function : \n";
    simple();       //function call函数调用

    cout << "main() is finished with the simple() function .\n";

    return 0;
}

//function definition(函数定义)
void simple()
{
    using namespace std;
    cout << "I'm but a simple function.\n";
}
